The present invention relates in general to a method for assembling composite blanks and, more particularly, to a method for aligning together individual discrete fold lines within separate carton blanks which are to be joined together in overlapping relationship, to provide a transparent window and the like, by a suitable bonding agent provided therebetween.
The method of the present invention may be used to manufacture a variety of products, including containers, window-type display packages and a number of other items for which one piece of rigid or semi-rigid material need to attached to another. In the manufacture of storage and/or package-type containers, e.g., products display packages and the like, such containers are generally constructed from one or more blanks of suitable material folded into the appropriate shape of the desired container by an apparatus constructed for such purpose. Ultimately, such blanks are secured in their folded shape by a bonding agent provided along their mating portions. One such novel container is constructed, in part, from a transparent plastic blank. Such package provides the retailer with a number of advantages over conventional all-cardboard packages, for example, visual display of the product.
One form of such partially transparent package is constructed from a carton blank of paperboard, cardboard or the like, which may have printing and/or decorative material applied to either face thereof with information in regard to the product, instructions for use of the product, the application of a trademark associated with the product, etc. The carton blank is typically provided with an opening through which a portion of the contained product may be viewed by the potential customer for selection and inspection. The construction of such a partially transparent package initially requires that a transparent plastic blank be positioned overlying the opening within the cardboard blank and bonded along a portion thereof in overlapping edge relationship about the perimeter of the opening Prior to the bonding operation, however, the transparent plastic blank and cardboard blank must be appropriately positioned with respect to each other, for example, in registration with any fold lines, openings, printing and/or decoration thereon.
There has heretofore been generally unknown an economical apparatus which is suitably adapted to perform the function of aligning one blank overlying the opening within a second blank in the manner required in the construction of the above-noted packages. As to one known apparatus, such apparatus is constructed to include a supporting vacuum table and blank feed hoppers using suction grabbers. This apparatus, in addition to being expensive, is laborious and time consuming when required to change over the set-up from one package forming operation to another. Further, a blank positioned on a vacuum table is capable of being inadvertently shifted which would effect the precision alignment required when joining to a second blank. Other known apparatuses and methods, for example, as disclosed in U.S. Pat. Nos. 4,518,379 and 4,549,878 are generally concerned with the bonding of individual blanks together along their respective sides, as opposed to overlying an opening within one of the individual blanks.
There is known from U.S. Pat. No. 2,625,085 an apparatus and method for assembling composite containers of the knock-down or collapsible folding type. A panel blank of transparent material is supplied from a hopper and placed onto a moving platform carried along by a conveyor. A pair of locating fingers secured to the conveyor capture the leading edge of the panel blank to cause aligned placement of the panel blank on the platform between a plurality of alignment pins which are secured to the platform and conveyor. An adhesive applicator of the wheel or disk type applies a layer of suitable adhesive along the lateral top and side portions of the panel blank as the conveyor and platform move the panel blank into proper registration under the adhesive applicator. A pair of side forming blanks of paperboard or cardboard material are aligned overlapping the lateral top side portions of the transparent panel blanks via the pins extending through alignment apertures provided in the side forming blanks. The side forming blanks are accordingly bonded to the panel blank by the adhesive provided therebetween and by the compressive force applied to the overlapping portion by a pressing device constructed of a plurality of pressure bearing blocks secured to a moving chain aligned over the overlapping portion. The thus formed planar composite container can then be folded along its appropriate score lines into the final container shape.
The composite container assembly apparatus and method of the above-described prior art construction includes a number of notable disadvantages. For example, the side forming blanks are required to be provided with a plurality of apertures to effect the alignment of the side forming blanks with the panel blank via the alignment pins. The presence and location of such apertures is considered objectionable where they are readily visible in the assembled container by detracting from the container's asthetic appearance. In many cases, the apparatus described in the prior art is not adaptable to the joining of blanks of certain configurations. For example, the known apparatus and method requires that some portion of the side forming blank overlap the edge of the panel blank, thereby precluding the arrangement of one blank falling entirely within the surface area of the other blank with no edge overlap as required by containers as to be described herein which are provided with a transparent plastic window.
Accordingly, it can be appreciated that there is an unsolved need for a method for joining individual blanks together which is specifically adapted for joining one blank wholly overlying another blank so as to form, for example, a transparent window having accurately aligned fold lines in a cheap, continuous and rapid manner, and at a minimum of expense.